The present invention relates to a switch using solenoid utilized in a radio frequency system. More particularly, it relates to a switch using solenoid capable of reducing the number of parts and total size of the switch.
Generally, there are a latching type switch, a fail-safe type switch and the like in switches using solenoid for a radio frequency system.
Hereinafter, conventional switches using solenoid will be schematically described, referring to FIGS. 1 and 2.
FIG. 1 shows a structure of the latching type switch using solenoid of the prior art.
As shown in FIG. 1, the conventional latching type switch has two solenoids 1 and 2 generating a magnetic field when electric current flows thereinto, a permanent magnet 3 located between the two solenoids 1 and 2, and a rocker 4 disposed under the solenoids 1 and 2. The rocker 4 is magnetized by the permanent magnet 3 to have N-S-N poles. Therefore, when electric current flows into the solenoid 1 or 2, the magnetized rocker 4 seesaws with center in the middle portion thereof and performs switching operation. That is, when electric current flows into the right solenoid 2 so that N pole (North Pole) is generated in the lower portion thereof, repulsion occurs between the right solenoid 2 and the right portion of the rocker 4 adjacent to the right solenoid 2. In this case, the right portion of the rocker 4 is descended and the left portion of the rocker 4 is ascended, so that the left portion of the rocker 4 is contacted to the bottom surface of the left solenoid 1.
On the contrary, when electric current flows into the left solenoid 1, the left portion of the rocker 4 is descended and the right portion of the rocker 4 is ascended, thereby contacting the right portion to the lower surface of the right solenoid 2.
Further, the conventional latching type switch has a plate spring 5 fixed to the lower portion of the rocker 4, two push pins 6 and 7 respectively located under both sides of the plate spring 5, and a plurality of connectors 8a, 8b and 8c located under the push pins 6 and 7. The push pins 6 and 7 have compression coil springs 6a and 7a respectively surrounding the upper portion thereof, and reeds 6b and 7b fixed to lower end thereof.
The plate spring 5 is moved in upward and downward directions together with the rocker 4. Therefore, when electric current flows into the right solenoid 2, the right portion of the plate spring 5 is descended by seesaw of the rocker 4 and presses the push pin 7. Simultaneously, the reed 7b fixed to lower end of the push pin 7 electrically connects the connectors 8b and 8c. In this state, when electric current flowing into the solenoid 2 is turned off and electric current flows into the left solenoid 1, the push pin 6 is pressed by seesaw of the rocker 4. Then, the compression coil spring 7a provides a restoring force for the push pin 7, thereby ascending the moved push pin 7 and separating the reed 7b from the connectors 8b and 8c. Further, the reed 6b fixed to the lower end of the push pin 6 electrically connects the connectors 8a and 8b. 
However, since the conventional latching type switch using solenoid requires two solenoids to move a rocker, the total size of the switch is large and the manufacturing cost is expensive.
Meanwhile, FIG. 2 shows a structure of the fail-safe type switch using solenoid of the prior art.
As shown in FIG. 2, the conventional fail-safe type switch comprises a solenoid 10 generating a magnetic field while electric current flows thereinto, a pushing rod 20 movably disposed at center portion of the solenoid 10, a rocker 30 located under the pushing rod 20, a compression spring 40 disposed on the rocker 30, and a plurality of connectors 61, 62 and 63. Further, under both sides of the rocker 30, two push pins 51 and 52 are movably disposed in upward and downward directions. Also, the push pins 51 and 52 have compression coil springs 51a and 52a respectively surrounding their peripheral surfaces, and reeds 51b and 52b fixed to their lower ends.
In this case, the pushing rod 20 is adjacent to the left portion of the rocker 30 and a lower end of the compression spring 40 is fixed to the right portion of the rocker 30.
In the state, when electric current flows into the solenoid 10 to generate the magnetic field, the pushing rod 20 descends and presses the left portion of the rocker 30. Then, the rocker 30 seesaws with center in the middle portion thereof, thereby pushing down the left push pin 51 so that the reed 51b fixed to the lower end of the push pin 51 electrically connects the connectors 61 and 62 and the compression spring 40 is compressed. The inclined state of the rocker 30 is continuously retained while electric current flows into the solenoid 10.
On the contrary, when electric current flowing into the solenoid 10 is turned off, the right portion of the rocker 30 is descended by restoring force of the compression spring 40 and the left portion of the rocker 30 is ascended. In this case, the right push pin 52 pressed by the right portion of the rocker 30 is descended so that the reed 52b electrically connects the connectors 62 and 63. Simultaneously, the left push pin 51 is ascended by restoring force of the compression coil spring 51a surrounding its peripheral portion.
However, since the conventional fail-safe type switch, for retaining the state descending the left push pin, must continuously flow electric current into the solenoid, the solenoid radiates high-temperature heat disturbing flow of electric current, thereby weakening the force moving the pushing rod. Therefore, since the size of the solenoid must be large in order to compensate the weakened force, total size of the fail-safe type switch is larger than the conventional latching type switch.
It is, therefore, an object of the present invention to provide a switch using solenoid capable of reducing the number of parts and a manufacturing cost of the switch, and minimizing total size of the switch.
In accordance with an aspect of the present invention, the switch of the present invention comprises a base having a plurality of grooves formed thereon; a plurality of solenoids having an armature respectively, and being respectively disposed above the grooves, wherein the armature is moved in upward and downward directions while an electric current flows into the solenoid; a plurality of connectors respectively disposed in the grooves; and a plurality of contact means for electrically connecting the connectors disposed in each of the grooves, and being movably disposed in the grooves to be pressed by the armature moved in downward direction.
Also, in another aspect of the present invention, solenoid used in the switch comprises a bobbin core generating a magnetic field while an electric current flows thereinto, and having a through hole formed vertically therethrough; a conductive coil for guiding the electric current, and being wound round peripheral surface of the bobbin core; an armature being magnetized by the magnetic field generated on the bobbin core, and being movably disposed within the through hole; a plurality of magnetization means generating a definite magnetic field, and being disposed at both ends of the bobbin core; a plurality of first magnetic substances disposed between the bobbin core and each of the magnetization means, and being magnetized by the magnetization means adjacent thereto; and a plurality of second magnetic substances respectively disposed at outer sides of the magnetization means, and being magnetized by the magnetization means adjacent thereto.